**3. Power Supply Reliability**

One of the main criteria for power supply efficiency is power supply reliability, which implies the continuous supply of electricity to consumers in accordance with an electricity consumption schedule [31]. In turn, a main indicator of the PS reliability is power supply restoration time [32]. It can include the following constituents: time for obtaining information, time for information recognition, time to repair failures, and time for connection harmonization [33]. That is, the PS restoration time can be determined by Equation (1):

$$t\_{\text{restor.}} = t\_{\text{obt.} \text{infor.}} + t\_{\text{rec.} \text{infor.}} + t\_{\text{repair}} + t\_{\text{harmonize}} \tag{1}$$

where


Each component of this equation can be further analyzed and contains several more time intervals, each of which ultimately has an impact on the overall power supply restoration time.

A time for obtaining information is denoted as an interval from the beginning of a failure until obtaining information on it by a dispatching service of a PS company [33]. This time includes the following intervals:

$$t\_{\text{cbt.inffor.}} = t\_{\text{inffor1}} + t\_{\text{inffor2}} + t\_{\text{inffor3}} \tag{2}$$

where


• *t*infor3—time for obtaining information on failures by means of third information links. This link can be a dispatcher that receives a network failure signal or an element of a network status monitoring or another automation system making a decision based on received information (for example, a data processing unit, a microprocessor, etc.). This time interval largely depends on the data transmission channel. Thus, a person (consumer) can report a failure by phone, e-mail, or in person to the dispatcher, etc. *t*infor3 will be different in each of these cases.

The information recognition time may be described using this equation: [33]

$$t\_{\text{rec.inffor.}} = t\_{\text{read.inffor}} + t\_{\text{dec}} + t\_{\text{search}} + t\_{\text{report}} \tag{3}$$

where


The repair time is an interval starting from the preparation of equipment to eliminate a failure up to the harmonization of the repair equipment [33]. This time can be represented as the following equation:

$$t\_{\text{repair}} = t\_{\text{repair,prepar}} + t\_{\text{repair,need}} + t\_{\text{repair,switching}} + t\_{\text{repair,perm1t}} + t\_{\text{repair,world}} + t\_{\text{repair,complete}} \tag{4}$$

where


The time of the connection harmonization *t*harmonize can be described using this equation [33]:

$$t\_{\text{harrnørize}} = t\_{\text{inf.transfer}} + t\_{\text{pre.conv.ct}} + t\_{\text{conv.ct}} + t\_{\text{erosure}} \tag{5}$$

where

• *t*inf.transfer—time required for information transfer time to a dispatching office the need to connect repaired equipment;


The literature positions indicate that data on the above time intervals are incomplete or often missed. However, the analysis of these time intervals reveals the potential to realize a reduction of the power supply restoration time that results in the power outages to consumers and the associated failures. Since the diagnostic methods and technical means for obtaining information about failures may be different [34], there are many factors that make it difficult to accurately determine the power supply restoration time and each of its constituents.

## **4. Results**
